Povysheva N V, Zaitsev A V, Rotaru D C, Gonzalez-Burgos G, Lewis D A, Krimer L S
University of Pittsburgh School of Arts and Sciences, Department of Psychiatry, Langley A210, Pittsburgh, PA 15260, USA.
J Neurophysiol. 2008 Oct;100(4):2348-60. doi: 10.1152/jn.90396.2008. Epub 2008 Jul 16.
Differences in the developmental origin and relative proportions of biochemically distinct classes of cortical neurons have been found between rodents and primates. In addition, species differences in the properties of certain cell types, such as neurogliaform cells, have also been reported. Consequently, in this study we compared the anatomical and physiological properties of parvalbumin (PV)-positive basket interneurons in the prefrontal cortex of macaque monkeys and rats. The somal size, total dendritic length, and horizontal and vertical spans of the axonal arbor were similar in monkeys and rats. Physiologically, PV basket cells could be identified as fast-spiking interneurons in both species, based on their short spike and high-frequency firing without adaptation. However, important interspecies differences in the intrinsic physiological properties were found. In monkeys, basket cells had a higher input resistance and a lower firing threshold, and they generated more spikes at near-threshold current intensities than those in rats. Thus monkey basket cells appeared to be more excitable. In addition, rat basket cells consistently fired the first spike with a substantial delay and generated spike trains interrupted by quiescent periods more often than monkey basket cells. The frequency of miniature excitatory postsynaptic potentials in basket cells was considerably higher in rats than that in monkeys. These differences between rats and monkeys in the electrophysiological properties of PV-positive basket cells may contribute to the differential patterns of neuronal activation observed in rats and monkeys performing working-memory tasks.
啮齿动物和灵长类动物在皮质神经元生物化学不同类别发育起源和相对比例上存在差异。此外，也有报道称某些细胞类型（如神经胶质样细胞）的特性存在种间差异。因此，在本研究中，我们比较了猕猴和大鼠前额叶皮质中小清蛋白（PV）阳性篮状中间神经元的解剖学和生理学特性。猕猴和大鼠的胞体大小、总树突长度以及轴突分支的水平和垂直跨度相似。在生理学上，基于PV篮状细胞短峰电位和高频放电且无适应性，在两个物种中均可将其识别为快速放电中间神经元。然而，我们发现了种间在内在生理学特性方面的重要差异。在猕猴中，篮状细胞具有更高的输入电阻和更低的放电阈值，并且在接近阈值电流强度时比大鼠产生更多的峰电位。因此，猕猴的篮状细胞似乎更易兴奋。此外，与猕猴篮状细胞相比，大鼠篮状细胞始终在相当长的延迟后才发出第一个峰电位，并且更频繁地产生被静息期打断的峰电位序列。大鼠篮状细胞中微小兴奋性突触后电位的频率比猕猴高得多。大鼠和猕猴在PV阳性篮状细胞电生理特性上的这些差异，可能有助于解释在执行工作记忆任务的大鼠和猕猴中观察到的神经元激活的不同模式。
